Chemical reactor and fuel cell system

ABSTRACT

A chemical reactor includes a first reaction section which has a first flow path and causes a first reaction in the first flow path. A heating section heats the first reaction section. A second reaction section has a second flow path and causes a second reaction in the second flow path by heat of the heating section transmitted via the first reaction section.

TECHNICAL FIELD

[0001] The present invention relates to a chemical reactor and a fuelcell system.

BACKGROUND ART

[0002] In a technical field of chemical reactions, a chemical reactorhas been known wherein a fluid material flows in a flow path formed in asubstrate so as to produce a desired fluid material by a chemicalreaction. Some of such conventional chemical reactors are small in sizeand have a flow path on a micron or millimeter scale which is formed ina small-sized substrate by use of a micro fabrication techniqueaccumulated by a semiconductor manufacturing technique for semiconductorintegrated circuits or the like, and PCT National Publication No.2001-524019 shows a chemical micro reactor with a plurality of laminatedsubstrates in which paths for a reacting fluid are formed. Such chemicalreactors promote a reaction by heating a reaction furnace, and thereaction furnace itself is small, thus offering advantages that uniformheat can be transmitted and a reaction can be uniformly induced.

[0003] In one chemical reactor which causes a plurality of reactions,suitable temperature for each reaction may differ, so that thetemperature needs to be changed locally.

[0004] Therefore, according to advantages of this invention, a chemicalreactor and a fuel cell system are provided which are capable ofperforming a plurality of chemical reactions and allow the entirereactor to be simplified and small in size.

DISCLOSURE OF INVENTION

[0005] The present invention provides a chemical reactor comprising:

[0006] a first reaction section which has a first flow path and causes afirst reaction in the first flow path;

[0007] a heating section which heats the first reaction section; and

[0008] a second reaction section which has a second flow path and causesa second reaction in the second flow path by heat of the heating sectiontransmitted via the first reaction section.

[0009] The heating section may heat a plurality of reaction sections,and especially when heating a plurality of reaction sections withdifferent suitable reaction temperatures, the heating section can heat,by heating one reaction section, heat the other reaction section via theone reaction section, thereby causing reactions in both the reactionsections at their suitable temperatures. A substrate in which the flowpaths are formed to cause reactions is preferable for this kind of heattransmission, but if thermal conductivity of the substrate is too good,temperature of the heat that reaches the reaction section requiring alower temperature might not be low enough. In such a case, it ispossible to adjust the temperature by providing slits in portions of thesubstrate to block the heat transmission.

BRIEF DESCRIPTION OF DRAWINGS

[0010]FIG. 1 is a block diagram showing essential parts of one exampleof a fuel cell system comprising a chemical reactor as one embodiment ofthis invention;

[0011]FIG. 2 is a perspective view of the essential parts of thechemical reactor shown in FIG. 1;

[0012]FIG. 3 is a cross sectional view along the line III-III of FIG. 2;

[0013]FIG. 4 is a transmitted plan view of a part corresponding to afirst substrate shown in FIG. 3;

[0014]FIG. 5 is a transmitted plan view of a part corresponding to asecond substrate shown in FIG. 3;

[0015]FIG. 6 is a transmitted plan view of a part corresponding to athird substrate shown in FIG. 3;

[0016]FIG. 7 is a graph showing changes with time of heatingtemperatures in a vaporization flow path, a reforming flow path and acarbon monoxide elimination flow path;

[0017]FIG. 8 is a schematic configuration diagram of a fuel cell sectionand a charging section shown in FIG. 1;

[0018]FIG. 9 is a cross sectional view similar to FIG. 3 showing theessential parts of the chemical reactor as another embodiment of thisinvention;

[0019]FIG. 10 is a transmitted plan view of a part corresponding to afourth substrate shown in FIG. 9;

[0020]FIG. 11 is a cross sectional view similar to FIG. 3 showing theessential parts of the chemical reactor as still another embodiment ofthis invention; and

[0021]FIG. 12 is a perspective view showing the partially broken fuelcell system comprising the chemical reactor of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

[0022] Next, a micro chemical reactor as one embodiment of thisinvention which is applied to a reforming reactor of a fuel reformingtype fuel cell system will be described. FIG. 1 is a block diagramshowing essential parts of one example of a fuel cell system 1. Thisfuel cell system 1 comprises a generation fuel section 2, a combustionfuel section 3, a micro chemical reactor 4, a fuel cell section 5 and acharging section 6.

[0023] The generation fuel section 2 includes a generation fuel storagecontainer in which a generation fuel 68 (e.g., a methanol solution) issealed, and supplies the generation fuel 68 to the micro chemicalreactor 4. The combustion fuel section 3 includes a combustion fuelstorage container in which a combustion fuel 69 (e.g., methanol) issealed, and supplies the combustion fuel 69 to the micro chemicalreactor 4. The micro chemical reactor 4 includes a generation fuelvaporization section 7 which vaporizes the fluid generation fuel 68, areforming reaction section 8 which reforms the vaporized generation fuel68, a carbon monoxide elimination section 9 which eliminates carbonmonoxide contained in the reformed fluid, a combustion section 10 forheating the generation fuel vaporization section 7, the reformingreaction section 8 and the carbon monoxide elimination section 9, and athin film heater section 11.

[0024]FIG. 2 is a perspective view of essential parts of the microchemical reactor 4. The micro chemical reactor 4 includes a firstsubstrate 12, a second substrate 13 and a third substrate 14 that aresmall-sized and laminated on each other. Three substrates 12 to 14 areaccommodated in an outer package constituted of a first outer panel 15and a second outer panel 16 that are joined to each other. In otherwords, concave parts 17 and 18 are formed in surfaces opposite to eachother of the first and second outer panels 15 and 16, and the first tothird substrates 12 to 14 are accommodated in these concave parts 17 and18. Glass is one example for a material of the first to third substrates12 to 14 and of the first and second outer panels 15 and 16, butsilicon, ceramic, metal simple substance (e.g., aluminum), metal alloys,metallic compounds and the like which have excellent workability may beused for the first substrate 12 and the third substrate 14 in whichafter-mentioned flow paths are formed.

[0025] At three predetermined portions of the first outer panel 15,round through-holes 24, 25 and 26 are formed into which first endportions of a generation fuel supply tubule 21, a generation productdischarge tubule 22 and an oxygen supply tubule 23 are inserted. Atthree predetermined portions of the second outer panel 16, roundthrough-holes 30, 31 and 32 are formed into which first end portions ofa combustion fuel supply tubule 27, a combustion gas discharge tubule 28and an oxygen supply tubule 29 are inserted. At predetermined portionsof the first outer panel 15, a plurality of round through-holes 34 areformed into which first end portions of a plurality of electrodes 33 areinserted. The plurality of electrodes 33 function as a signal wire groupfor electrically controlling the thin film heater or the heater section11, which heats the generation fuel vaporization section 7 and thereforming reaction section 8 of the micro chemical reactor 4 describedlater, and for electrically controlling a first micro pump 46 (see FIG.1), and also function as wires for sending and receiving signalsincluding temperature data detected by a thermometer section 19 whichdetects temperature in the micro chemical reactor 4.

[0026]FIG. 3 is a cross sectional view along the line III-III of FIG. 2and the line III-III of FIG. 4. FIG. 4 is a transmitted plan view of apart corresponding to the first substrate 12, FIG. 5 is a transmittedplan view of a part corresponding to the second substrate 13; and FIG. 6is a transmitted plan view of a part corresponding to a third substrate14. On inner wall surfaces of the concave part 17 of the first outerpanel 15 and the concave part 18 of the second outer panel 16, heatradiation prevention films 35, which are formed of a metal such as Au,Ag or Al with high heat ray reflectivity, are provided except forportions corresponding to the round transmitting holes 24, 25, 26, 30,31, 32 and 34 shown in FIG. 2.

[0027] On outermost surfaces of the first to third substrates 12 to 14,that is, on an upper surface (surface opposite to a side facing thesecond substrate 13) and side surfaces of the first substrate 12, sidesurfaces of the second substrate 13, and a lower surface (surfaceopposite to a side facing the second substrate 13) and side surfaces ofthe third substrate 14, a heat generation prevention film 36 formed ofthe same material as above is provided except for the portionscorresponding to the round transmitting holes 24, 25, 26, 30, 31, 32 and34 shown in FIG. 2 and except for portions corresponding to slits 56described later.

[0028] A space or clearance 37 is provided between the heat generationor release prevention film 36 laid on the outermost surfaces of thefirst to third substrates 12 to 14 and the heat generation preventionfilms 35 laid on the inner surfaces of the first and second outer panels15 and 16 so that the least heat released from the first to thirdsubstrates 12 to 14 is transmitted to the first and second outer panels15 and 16. At a plurality of predetermined portions of the space 37, aplurality of pressure resistant spacers 38 is provided to hold the firstto third substrates 12 to 14 and to maintain the width of the aperture37. Two of the plurality of pressure resistant spacers 38 are providedfor each surface of the first to third substrates 12 to 14.

[0029] The aperture 37 inhibits the heat generated as described later inthe first to third substrates 12 to 14 from being released into theatmosphere, and a vacuum is formed in the aperture 37 or a gas with lowthermal conductivity (such as atmospheric air, carbon dioxide gas orchlorofluorocarbon) fills the aperture 37. The heat release preventionfilms 35 and 36 inhibit heat generation from the outermost surfaces ofthe first to third substrates 12 to 14 to the outside of the first andsecond outer panels 15 and 16, and any one of the heat generationprevention films may be dispensed with.

[0030] As shown in FIG. 4, a vaporization flow path groove 57, areforming flow path groove 58 and a carbon monoxide elimination flowpath groove 59 are continuously formed in the inner surface of the firstsubstrate 12. The vaporization flow path groove 57 of the firstsubstrate 12 and an opposite surface of the second substrate 13 arecombined with each other to form a vaporization flow path 41 in whichthe fluid generation fuel 68 flows while being vaporized. The reformingflow path groove 58 of the first substrate 12 and the opposite surfaceof the second substrate 13 are combined with each other to form areforming flow path 42 in which the fluid resulting from the vaporizedgeneration fuel 68 flows while being reformed. The carbon monoxideelimination flow path groove 59 of the first substrate 12 and theopposite surface of the second substrate 13 are combined with each otherto form a carbon monoxide elimination flow path 43 in which the fluidresulting from the reformed generation fuel 68 flows while carbonmonoxide contained therein is being eliminated. The vaporization flowpath 41 is provided making about one round and a half from a lower leftcorner in a clockwise direction with a total length of 1 cm or more and10 cm or less around a peripheral part of the inner surface (surfaceopposite to the second substrate 13) of the first substrate 12. Themeandering reforming flow path 42 is provided continuously from thevaporization flow path 41 with a total length of 3 cm or more and 20 cmor less in a central part of the inner surface of the first substrate12, as indicated by hatching. The suitably meandering carbon monoxideelimination flow path 43 is provided continuously from the reformingflow path 42 with a total length of 3 cm or more and 20 cm or less onthe inner surface of the first substrate 12 except for the peripheralpart and central part. The width and depth of the vaporization flow path41, the reforming flow path 42 and the carbon monoxide elimination flowpath 43 are both about 500 μm or less as one example. In this way, aterminal end of the vaporization flow path 41 is coupled to a startingend of the reforming flow path 42, and a terminal end of the reformingflow path 42 is coupled to a starting end of the carbon monoxideelimination flow path 43.

[0031] The vaporization flow path 41 constitutes the generation fuelvaporization section 7, which is a reaction furnace where the generationfuel 68 in liquid form is vaporized. The vaporization flow path 41 isnot provided with a reaction catalyst therein. The reforming flow path42 constitutes the reforming reaction section 8, which is a reactionfurnace where the generation fuel 68 vaporized by the generation fuelvaporization section 7 is reformed. In this case, a surface of thereforming flow path groove 58 in the reforming flow path 42 is providedwith a reforming catalyst layer 44 (see FIG. 3) which is formed ofreforming catalyst such as Cu or ZnO, supported by a porous support filmsuch as Al₂O₃. The carbon monoxide elimination flow path 43 constitutesa reaction furnace of the carbon monoxide elimination section 9, whichis a reaction furnace where carbon monoxide contained in a by-productproduced by the reforming reaction section 8 is eliminated. In thiscase, a surface of the carbon monoxide elimination flow path groove 59in the carbon monoxide elimination flow path 43 is provided with aselective oxidative catalyst layer 45 (see FIG. 3) which is formed ofreforming catalyst such as PT, supported by a porous support film suchas Al₂O₃.

[0032] The first micro pump 46 is provided at a predetermined positionin the lower left corner of the inner surface of the first substrate 12.The first micro pump 46 takes in from the generation fuel section 2 anamount of generation fuel 68 corresponding to a signal which is providedfrom a control circuit section 20 (see FIG. 1) in the fuel cell system 1via the electrodes 33 or the like, and then supplies it to the startingend of the vaporization flow path 41 via the generation fuel supplytubule 21.

[0033] The first micro pump 46 may be ultra small and injects a liquidin a form of particles from a nozzle while controlling its injectionamount. The first micro pump 46 is preferably, for example, an injectorwhich heats a liquid in the nozzle so as to inject the liquid in aparticle form by pressure of air bubbles in the nozzle produced by filmboiling; an injector (so-called piezojet method) which injects liquid inthe nozzle in the particle form by pressure waves caused in the nozzledue to deformation of an electrostriction element (piezo element); or aninjector (so-called electrostatic jet method) which injects liquid inthe nozzle in the particle form by vibration due to electrostatic forceof a diaphragm in the nozzle. The same applies to a second micro pump 47or the like described later.

[0034] One end of the oxygen supply tubule 23 is connected to apredetermined portion 43 a in the vicinity of the starting end of thecarbon monoxide elimination flow path 43. By driving a fourth micro pump49 provided outside the micro chemical reactor 4, oxygen (air) in theatmosphere is supplied to the predetermined portion 43 a in the vicinityof the starting end of the carbon monoxide elimination flow path 43 viathe oxygen supply tubule 23. A third micro pump 48 controls a supplyamount of oxygen in accordance with a signal provided from the controlcircuit section 20 in the fuel cell system 1. One end of the generationproduct discharge tubule 22 is connected to a predetermined portion 43 bin the vicinity of the terminal end of the carbon monoxide eliminationflow path 43.

[0035] As shown in FIG. 3 and FIG. 5, the thin film heater section 11comprising a heat generation resistive element thin film such as TaSiOxor TaSiOxN which generates heat in accordance with a voltage applied bya signal from the control circuit section 20 is provided at a portionopposite to the reforming flow path 42 on a surface of the secondsubstrate 13 opposite to the first substrate 12. The thin film heatersection 11 is disposed in the reforming flow path 42, utilized as a heatsource required for an initial state of a reforming reaction in thereforming flow path 42 of the reforming reaction section 8, controlstemperature in the reforming flow path 42, and is also utilized as aheat source required for an initial state of chemical reactions in thevaporization flow path 41 of the generation fuel vaporization section 7and in the carbon monoxide elimination flow path 43 of the carbonmonoxide elimination section 9.

[0036] Heating in the reforming flow path 42 is achieved by heat energymainly generated in the combustion section 10 (details of which will bedescribed later) shown in FIG. 1. The thin film heater 11 is usedsecondarily. In other words, the combustion section 10 is mainly thesource of heat transmitted to promote reactions in the vaporization flowpath 41 of the generation fuel vaporization section 7, in the reformingflow path 42 of the reforming reaction section 8, and in the carbonmonoxide elimination flow path 43 of the carbon monoxide eliminationsection 9. The thin film heater 11 has a fine adjusting function so thatsuitable temperatures are obtained in the vaporization flow path 41, thereforming flow path 42 and the carbon monoxide elimination flow path 43in accordance with a signal provided from the control circuit section 20in the fuel cell system 1 via the electrodes 33 or the like.

[0037] The thin film thermometer section 19 constituted by a thin filmthermometer or a semiconductor thin film thermocouple is provided in thevicinity of the reforming flow path 42. The thin film thermometersection 19 detects temperature in the vaporization flow path 41 of thegeneration fuel vaporization section 7 heated by the combustion section10 and the thin film heater 11, temperature in the reforming flow path42 of the reforming reaction section 8 and temperature in the carbonmonoxide elimination flow path 43 of the carbon monoxide eliminationsection 9, and then provides their temperature detection signals to thecontrol circuit section 20 in the fuel cell system 1 via the electrodes33 or the like. On the basis of these temperature detection signals, thecontrol circuit section 20 in the fuel cell system 1 controls the heatgeneration of the thin film heater 11 so that suitable temperatures areobtained in the vaporization flow path 41 of the generation fuelvaporization section 7, in the reforming flow path 42 of the reformingreaction section 8 and in the carbon monoxide elimination flow path 43of the carbon monoxide elimination section 9.

[0038] The above-mentioned thin film heater section 11 including theheat generation resistive element thin film can serve also as theaccurate thermometer section 19 as long as it shows a resistance changewhich is linear with respect to a heating temperature t and which islarge. In other words, at least two terminals connected to theelectrodes 33 are set to be connected to both ends of the thin filmheater section 11, and a voltage is applied across these two terminals,thereby heating the thin film heater section 11. In this case, becauseresistance of the thin film heater section 11 is dependent on theheating temperature, the control circuit section 20 can read aresistance change in the thin film heater section 11 by reading a changeof the voltage across the two terminals via the electrodes 33. Such aconfiguration enables a higher density package.

[0039] Around a peripheral part of the inner surface (surface facing thesecond substrate 13) of the third substrate 14, a combustion fuelvaporization flow path groove 51 is continuously cut in a clockwisedirection making about one round and a half in such a manner that itoverlaps and extends along the reforming flow path 42 of the firstsubstrate 12 as shown in FIG. 6. As indicated by hatching in FIG. 6, acombustion flow path groove 52 is formed meanderingly in such a mannerthat it overlaps and extends along the reforming flow path 42 of thefirst substrate 12. A linear discharge flow path groove 53 is cut at thelower left of the central part of the inner surface of the thirdsubstrate 14. A terminal end of the combustion fuel vaporization flowpath groove 51 communicates with a starting end of the combustion flowpath groove 52. A terminal end of the combustion flow path groove 52communicates with a starting end of the discharge flow path groove 53.The combustion fuel vaporization flow path groove 51 of the thirdsubstrate 14 and the opposite surface of the second substrate 13 arecombined with each other to form a combustion fuel vaporization flowpath 75. The combustion flow path groove 52 of the third substrate 14and the opposite surface of the second substrate 13 are combined witheach other to form a combustion flow path 76. The discharge flow pathgroove 53 of the third substrate 14 and the opposite surface of thesecond substrate 13 are combined with each other to form a dischargeflow path 77. In the combustion flow path 76 among the above flow paths,a combustion catalyst layer 54 (see FIG. 3) made of Pt, Au, Ag and thelike is provided in the combustion flow path groove 52. The combustionflow path 76 functions as the combustion section 10. The width and depthof the combustion fuel vaporization flow path 75, the combustion flowpath 76, and the discharge flow path 77 are both about 500 μm or less asone example.

[0040] The second micro pump 47 is provided at a predetermined positionin the lower left corner of the inner surface of the third substrate 14.The second micro pump 47 is automatically supplied with the combustionfuel 69 from the combustion fuel section 3 via the combustion fuelsupply tubule 27 by a capillary phenomenon or by driving of the secondmicro pump 47. The second micro pump 47 injects the combustion fuel 69into an starting end of the combustion fuel vaporization flow path 75while controlling its injection amount in accordance with a signalprovided from the control circuit section 20 in the fuel cell system 1via the electrodes 33 or the like.

[0041] At a predetermined portion 75 a of a terminal end of thecombustion fuel vaporization flow path 75, the round transmitting hole32 is formed in the second outer panel 16 so as to communicate with oneend of the oxygen supply tubule 29 shown in FIG. 2, and a through-holeis formed in the third substrate 14. By driving the third micro pump 48provided outside the micro chemical reactor 4, oxygen (air) in theatmosphere is supplied to the predetermined portion 75 a in the vicinityof the terminal end of the combustion fuel vaporization flow path 75 viathe oxygen supply tubule 29. The third micro pump 48 controls a supplyamount of oxygen in accordance with a signal provided from the controlcircuit section 20 in the fuel cell system 1. One end of the combustiongas discharge tubule 28 shown in FIG. 2 is connected to the terminal endof the discharge flow path 77. The other end of the combustion gasdischarge tubule 28 communicates with the outside of the fuel cellsystem 1, and is open to the atmosphere.

[0042] Here, as shown in FIG. 3 to FIG. 6, the reforming flow path 42,the thin film heater 11 and the combustion flow path 76 are disposed atthe same position in a planar view. The width of the thin film heater 11is narrower than that of the reforming flow path 42 so that it can bereceived in the reforming flow path groove 58. In parts of the first tothird substrates 12 to 14 on a periphery of an area where the reformingflow path 42, the thin film heater 11 and the combustion flow path 76are disposed, four slits 56 are respectively formed. The slits 56constitute a low efficiency thermal conduction section whose thermalconductivity is lower than those of the first to third substrates 12 to14, and carry out an adjustment so that heat energy generated by thecombustion section 10 and the thin film heater 11 as described laterwill not be excessively transmitted to the vaporization flow path 41 andthe carbon monoxide elimination flow path 43 via the first to thirdsubstrates 12 to 14 to cause overheat in the vaporization flow path 41and the carbon monoxide elimination flow path 43. The slits 56 arefilled with a gas with low thermal conductivity (such as atmosphericair, carbon dioxide gas or chlorofluorocarbon) or have an atmospheredepressurized to 1 Pa or less.

[0043] Next, operation of the micro chemical reactor 4 having the aboveconfiguration will be described. First, when the combustion fuel 69(e.g., methanol) in liquid form is supplied from the second micro pump47 to the starting end of the combustion fuel vaporization flow path 75,heat energy due to only initial heat generation of the thin film heater11 is transmitted to the combustion fuel vaporization flow path groove51 via the first to third substrates 12 to 14, thereby heating theinside of the combustion fuel vaporization flow path 75 to apredetermined temperature. In the combustion fuel vaporization flow path75, the combustion fuel 69 is heated and thus vaporized to become acombustion fuel gas (e.g., CH₃OH if the combustion fuel 69 is methanol).

[0044] This produced combustion fuel gas (CH₃OH) is mixed with oxygen(air) supplied via the oxygen supply tubule 29 from the atmosphere atthe predetermined portion 75 a in the vicinity of the terminal end ofthe combustion fuel vaporization flow path 75. When this mixed gas(CH₃OH+O₂) is supplied into the combustion flow path 76 having thecombustion catalyst layer 54, the supplied mixed gas is combusted on thecombustion catalyst layer 54 by a combustion reaction indicated by thefollowing equation (1), and heat energy is generated by this combustion.

CH₃OH+(3/2)O₂→CO₂+2H₂O  (1)

[0045] This heat energy mainly heats the inside of the reforming flowpath 42, and is then transmitted to the first to third substrates 12 to14, and heats the inside of the carbon monoxide elimination flow path 43of the carbon monoxide elimination section 9 and the inside of thevaporization flow path 41 of the generation fuel vaporization section 7.After that, the thin film heater 11 stops or reduces only the initialheat generation, and the subsequent heat generation is controlled by thecontrol circuit section 20 in the fuel cell system 1 in accordance withthe temperature detection signal of the thermometer section 19. On theother hand, the combustion gas (CO₂) on a right side of the aboveequation (1) is released into the atmosphere via the discharge flow path77 and the combustion gas discharge tubule 28. By-product water iscollected by a by-product collecting section 109 described later.

[0046] Here, a required heating temperature in the reaction furnace ofthe reforming reaction section 8 constituted by the reforming flow path42 is about 250 to 320° C., and a required heating temperature in thereaction furnace of the carbon monoxide elimination section 9constituted by the carbon monoxide elimination flow path 43 is lowerthan the above and is about 160 to 220° C., and a required heatingtemperature in the reaction furnace of the generation fuel vaporizationsection 7 constituted by the vaporization flow path 41 is still lowerthan the above and is about 100 to 150° C. The vaporization flow path 41may be provided with a metal film therein whose thermal conductivity ishigher than those of the first substrate 12 and the second substrate 13to effectively absorb the heat from the heat source and emit it into theflow path.

[0047] As described above, the combustion flow path 76 of the combustionsection 10 and the thin film heater 11, which are the heat sources, aredisposed in the central part of the first to third substrates 12 to 14,and the reforming flow path 42 of the reforming reaction section 8 whoserequired heating temperature (about 250 to 320° C.) is the highest isdisposed in the central part, and outside this, the carbon monoxideelimination flow path 43 of the carbon monoxide elimination section 9whose required heating temperature (about 160 to 220° C.) is lower thanthe above is disposed, and further outside this, the vaporization flowpath 41 of the generation fuel vaporization section 7 whose requiredheating temperature (about 100 to 150° C.) is still lower is disposed.In this way, the distance from the combustion section 10 is shorter inthe order of the reforming flow path 42, the carbon monoxide eliminationflow path 43 and the vaporization flow path 41, and the distance fromthe thin film heater 11 is shorter in the order of the reforming flowpath 42, the carbon monoxide elimination flow path 43 and thevaporization flow path 41. Thus, the heat energy generated in thecombustion section 10 and the thin film heater 11 first heats thereforming reaction section 8 at its required heating temperature. Thetemperature decreases as the heat energy is transmitted through thefirst to third substrates 12 to 14. When it reaches the carbon monoxideelimination section 9 positioned on a periphery of the reformingreaction section 8, the temperature lowers to the required heatingtemperature of the carbon monoxide elimination section 9. Finally, whenit reaches the generation fuel vaporization section 7 positioned outsidethe carbon monoxide elimination section 9 via the first to thirdsubstrates 12 to 14, the temperature lowers to the required heatingtemperature of the generation fuel vaporization section 7. Thus, thegeneration fuel vaporization section 7, the reforming reaction section 8and the carbon monoxide elimination section 9 are respectively heated totheir suitable temperatures.

[0048] While the heating temperature is easily controlled in the thinfilm heater 11, it is difficult to accurately control the heatingtemperature in the reforming flow path 42 by control of the combustionreaction in the combustion flow path 76 of the combustion section 10.Therefore, the heat energy generated by the combustion reaction in thecombustion flow path 76 is brought to, for example, about 190 to 300°C., which is slightly lower than the required heating temperature (about250 to 320° C.) in the reforming flow path 42 of the reforming reactionsection 8. Then, the control circuit section 20 receives information onthe temperature in the reforming flow path 42 from the electrodes 33 andfeeds back electric power to be supplied to the thin film heater 11, sothat the required heating temperature can be rapidly reached, and finetemperature control that continuously maintains the required temperaturecan be achieved, whereby the generation fuel vaporization section 7.Accordingly, the reforming reaction section 8 and the carbon monoxideelimination section 9 can be kept within the required heatingtemperatures.

[0049] If materials for the first to third substrates 12 to 14 areglass, silicon, ceramic, metals and the like, their thermalconductivities are significantly higher than that of the air, so thatwithout any measures to be taken, the temperature becomes about the samethroughout the first to third substrates 12 to 14. Therefore, asdescribed above, the four slits 56 are provided in the parts of thefirst to third substrates 12 to 14 at the periphery of the area wherethe combustion flow path 76 of the combustion section 10, the thin filmheater 11, and the reforming flow path 42 of the reforming reactionsection 8 are disposed, and a vacuum is formed in the atmosphere insidethese slits 56 or a gas with low thermal conductivity (such asatmospheric air, carbon dioxide gas or chlorofluorocarbon) fills theatmosphere inside these slits 56, whereby it is possible to inhibit theheat energy generated in the combustion section 10 and the thin filmheater 11 from being excessively transmitted into the carbon monoxideelimination flow path 43 and the vaporization flow path 41 via the firstto third substrates 12 to 14. Porous structures with heat transmissionproperties made of ceramic or the like may be contained in the slits 56.

[0050] In the case of only the first to third substrates 12 to 14,because their sizes are small and a ratio of a surface area to a volumeis large, the heat energy released into the atmosphere becomes large,and utilization efficiency of heat energy becomes lower. Therefore, asdescribed above, the first to third substrates 12 to 14 are covered withthe first and second outer panels 15 and 16, and the space 37 isprovided therebetween, and then a vacuum is formed in or a gas with lowthermal conductivity (such as atmospheric air, carbon dioxide gas,chlorofluorocarbon or inactive gas) fills the atmosphere of the space37, and then the outer surfaces of the first to third substrates 12 to14 are covered with the heat generation prevention film 36 and the innersurfaces of the first outer panel 15 and the second outer panel 16 arecovered with the heat generation prevention film 35, whereby it becomespossible to inhibit the heat energy generated by the combustion section10 and the thin film heater 11 from being released into the atmosphere,and to improve efficiency in utilization of heat energy.

[0051] In the case where the first to third substrates 12 to 14 arecovered with the first and second outer panels 15 and 16 to reduce theheat released into the atmosphere, if the temperature in the first andsecond outer panels 15 and 16 increases too high and it is difficult tomaintain temperature distribution in the first to third substrates 12 to14 at an initial value even after transmitted heat is adjusted by theslits 56, all or part of the plurality of pressure resistant spacers 38is formed of a material with high thermal conductivity such as a metalor glass, and the heat is moderately released outside the micro chemicalreactor 4 via the pressure resistant spacers 38. Thus, the temperaturedistribution in the first to third substrates 12 to 14 can be brought tothe initial value. Furthermore, when the heat generation of the thinfilm heater 11 and the combustion section 10 is stopped, such heatrelease by use of the pressure resistant spacers 38 can serve to rapidlylower the temperature in the first and second outer panels 15 and 16.

[0052] In this way, the fuel cell system 1 adjusts the heat released tothe outside thereof via the pressure resistant spacers 38, so that thetemperature distribution in the first to third substrates 12 to 14 canbe maintained at the initial value.

[0053] Here, after heated with the heat energy generated in thecombustion section 10 and the heat energy generated in the thin filmheater 11, changes with time of the respective heating temperatures inthe vaporization flow path 41, the reforming flow path 42 and the carbonmonoxide elimination flow path are checked, thereby obtaining resultsshown in FIG. 7. In FIG. 7, a solid line indicates the heatingtemperature in the reforming flow path 42 of the reforming reactionsection 8, a broken line indicates the heating temperature in the carbonmonoxide elimination flow path 43 of the carbon monoxide eliminationsection 9, and a dashed line indicates the heating temperature in thevaporization flow path 41 of the generation fuel vaporization section 7.

[0054] As apparent from FIG. 7, after about 40 seconds from the start ofheat generation, each heating temperature is almost stabilized, and theheating temperature in the reforming flow path 42 indicated by the solidline can be about 300° C., and the heating temperature in the carbonmonoxide elimination flow path 43 indicated by the broken line can beabout 200° C., and further the heating temperature in the vaporizationflow path 41 indicated by the dashed line can be about 150° C.

[0055] In this way, by heating with the heat energy generated in thecombustion flow path 76 of the combustion section 10 and the heat energygenerated by the thin film heater 11, the heating temperature in thereaction furnace of the reforming reaction section 8 constituted by thereforming flow path 42 is brought to the required heating temperature ofabout 250 to 320° C., the heating temperature in the reaction furnace ofthe carbon monoxide elimination section 9 constituted by the carbonmonoxide elimination flow path 43 is brought to the required heatingtemperature of about 160 to 220° C., and the heating temperature in thereaction furnace of the generation fuel vaporization section 7constituted by the vaporization flow path 41 is brought to the requiredheating temperature of about 100 to 150° C.

[0056] When the generation fuel 68 in liquid form (e.g., a methanolsolution) is supplied to the starting end of the vaporization flow path41 from the first micro pump 46, the generation fuel 68 is vaporized inthe vaporization flow path 41 which is heated to the required heatingtemperature of about 100 to 150° C. inside, and the generation fuel gas(e.g., CH₃OH(g)+H₂O(g) when the generation fuel 68 is a methanolsolution) is generated. In other words, the generation fuel gas(CH₃OH+H₂O) is generated in the generation fuel vaporization section 7.

[0057] This generated generation fuel gas (CH₃OH+H₂O) is supplied intothe reforming flow path 42. In other words, the generation fuel gas(CH₃OH+H₂O) generated in the generation fuel vaporization section 7 issupplied to the reforming reaction section 8. Then, when the generationfuel gas (CH₃OH+H₂O) is supplied into the reforming flow path 42 havingthe reforming catalyst layer 44, an endothermal reaction as indicated bythe following equation (2) is caused in the reforming flow path 42because the inside of the reforming flow path 42 is heated to therequired heating temperature of about 250 to 320° C., thereby producinghydrogen and by-product carbon dioxide.

CH₃OH+H₂O→3H₂+CO₂→(2)

[0058] At this time, a slight amount of carbon monoxide might beproduced in the reforming flow path 42. These products (hydrogen, carbondioxide and the slight amount of carbon monoxide) are supplied into thecarbon monoxide elimination flow path 43. In other words, hydrogen,carbon dioxide and the slight amount of carbon monoxide produced in thereforming reaction section 8 are supplied to the carbon monoxideelimination section 9. These products (hydrogen, carbon dioxide and theslight amount of carbon monoxide) are mixed with oxygen (air) suppliedvia the oxygen supply tubule 23 from the atmosphere outside the fuelcell system 1 at the predetermined portion 43 a in the vicinity of thestarting end of the carbon monoxide elimination flow path 43. In thiscase, a check valve is provided in the oxygen supply tubule 23, so thatthe products do not leak outside the fuel cell system 1.

[0059] When a mixture (hydrogen, carbon dioxide, the slight amount ofcarbon monoxide and oxygen) is supplied into the carbon monoxideelimination flow path 43 having the selective oxidative catalyst layer45, carbon monoxide and oxygen are reacted in carbon monoxideelimination flow path 43 whose inside is heated to the required heatingtemperature of about 160 to 220° C., thereby producing carbon dioxide asindicated by the following equation (3).

CO+(½)O₂→O₂+CO₂  (3)

[0060] Finally, most of fluids reaching the terminal end of the carbonmonoxide elimination flow path 43 that constitutes the reaction furnaceof the carbon monoxide elimination section 9 are hydrogen and carbondioxide. These products are discharged outside via the generationproduct discharge tubule 22, but, out of these products, carbon dioxideis separated from hydrogen by a separation section 66 (see FIG. 1) to bereleased outside the fuel cell system 1. Therefore, hydrogen and watervapor are supplied from the carbon monoxide elimination section 9 to thefuel cell section 5.

[0061] As described above, in the micro chemical reactor 4 having theabove configuration, in the inner surface of the first substrate 12, thevaporization flow path 41 which constitutes the reaction furnace of thegeneration fuel vaporization section 7, the reforming flow path 42 whichconstitutes the reaction furnace of the reforming reaction section 8 andthe carbon monoxide elimination flow path 43 which constitutes thereaction furnace of the carbon monoxide elimination section 9 arecontinuously provided within the same substrate, so that three chemicalreactions can be successively caused in three kinds of flow paths, i.e.,the vaporization flow path 41, the reforming flow path 42 and the carbonmonoxide elimination flow path 43, thereby enabling the whole reactor tobe simple and compact.

[0062] Furthermore, the combustion flow path 76 of the combustionsection 10 and the thin film heater 11, which are the heat sources, aredisposed in the central part of the first to third substrates 12 to 14,and the reforming flow path 42 of the reforming reaction section 8 whoserequired heating temperature (about 250 to 320° C.) is the highest isdisposed in the central part, and outside this, the carbon monoxideelimination flow path 43 of the carbon monoxide elimination section 9whose required heating temperature (about 160 to 220° C.) is lower thanthe above is disposed, and further outside this, the vaporization flowpath 42 of the generation fuel vaporization section 7 whose requiredheating temperature (about 100 to 150° C.) is still lower is disposed,and the slits 56 adjust the transmitted heat, whereby efficient heatingcan be achieved in the vaporization flow path 41, the reforming flowpath 42 and the carbon monoxide elimination flow path 43 so as to reformthe generation fuel 68.

[0063] Next, the fuel cell section 5 and the charging section 6 will bedescribed. The fuel cell section 5 is constituted by a solidmacromolecule type fuel cell as shown in FIG. 8. More specifically, thefuel cell section 5 has a cathode 61 is formed of a carbon electrode towhich catalysts such as Pt and C are stuck, an anode 62 formed of acarbon electrode to which catalysts such as Pt, Ru and C are stuck. Afilm-like ion conductive film 63 is placed between the cathode 61 andthe anode 62, thereby supplying electric power to the charging section 6constituted of a secondary cell or a capacitor provided between thecathode 61 and the anode 62.

[0064] In this case, a space section 64 is provided outside the cathode61. Hydrogen and water are supplied into the space section 64 via theseparation section 66, and thus hydrogen and water reach the cathode 61.Another space section 65 is provided outside the anode 62. Oxygen takenin from the atmosphere via the micro pump is supplied into the spacesection 65, and thus oxygen is supplied to the anode 62.

[0065] Hydrogen ions (proton; H⁺) in which electrons (e⁻) are separatedfrom hydrogen are produced on a side of the cathode 61 as shown in thefollowing equation (4), and pass to a side of the anode 62 via the ionconductive film 63, and then the cathode 61 takes out electrons (e⁻)therefrom to allow a current to flow.

H₂→2H⁺+2e⁻  (4)

[0066] On the other hand, electrons (e⁻) supplied by way of the chargingsection 6, hydrogen ions (H+) which have passed through the ionconductive film 63, and oxygen cause a reaction on the side of the anode62, thereby producing by-product water, as shown in the followingequation (5).

2H⁺+(½)O₂+2^(e−)→H₂O  (5)

[0067] The series of electrochemical reactions described above (equation(4) and equation (5)) proceed under an environment at a relatively lowtemperature of about room temperature to 80° C., and water is basicallythe only by-product except for electric power. The electric powergenerated by the fuel cell section 5 is supplied to the charging section6, whereby the charging section 6 is charged. Water as the by-productproduced by the fuel cell section 5 is once taken in by a by-producttake-in section 107, and is subsequently collected by a by-productcollecting section 109 in a fuel storage module 102 described later. Theby-product take-in section 107 may supply a proper amount of taken-inwater to the reforming reaction section 8 and the carbon monoxideelimination section 9 as necessary.

[0068] Here, in the micro chemical reactor 4 having the aboveconfiguration, the first to third substrates 12 to 14 that are laminatedon each other are accommodated in the first and second outer panels 15and 16 that are joined to each other, which makes it possible to savespace and design the size and shape of the fuel cell system 1 itself tocorrespond to the size and shape of multipurpose chemical cells such asdry cells.

[0069] In the embodiment described above, the case where the thin filmheater 11 is used as part of the heat source has been described, whichis not limited. For example, another embodiment of this invention shownin FIG. 9 and FIG. 10 may be applied. FIG. 9 is a cross sectional viewsimilar to FIG. 3 showing the essential parts of the micro chemicalreactor as another embodiment of this invention, and FIG. 10 is atransmitted plan view of a part corresponding to a fourth substrate 71.

[0070] In this case, the fourth substrate 71 is provided between thefirst substrate 12 and the second substrate 13. The thin film heater isnot provided in the central part of the surface of the second substrate13 opposite to the fourth substrate 71. Instead, a thermal fluid flowpath groove 67 is cut in the central part of the surface of the fourthsubstrate 71 opposite to the second substrate 13. The thermal fluid flowpath groove 67 and the second substrate 13 are combined with each otherto form a thermal fluid flow path 72. The thermal fluid flow path 72 isprovided meanderingly, similarly to the reforming flow path 42 and thecombustion flow path 76. An inflow side flow path 73 is provided in thethermal fluid flow path groove 67 on an inflow side of the thermal fluidflow path 72, and an outflow side flow path 74 is provided in thethermal fluid flow path groove 67 on an outflow side.

[0071] An inflow side end of the inflow side flow path 73 is disposed atsuch a position that it does not overlap the terminal end of thevaporization flow path 41 shown in FIG. 4, and is connected to one endof a thermal fluid supply tubule that is inserted into the roundtransmitting hole provided at predetermined portions of the first outerpanel 15 and the first substrate 12, which is not shown in the drawing.An outflow side end of the outflow side flow path 74 is disposed at sucha position that it does not overlap the starting end of the carbonmonoxide elimination flow path 43 shown in FIG. 4, and is connected toone end of a thermal fluid discharge tubule that is inserted into theround transmitting hole provided at other predetermined portions of thefirst outer panel 15 and the first substrate 12, which is not shown inthe drawing.

[0072] The other end of the thermal fluid supply tubule and the otherend of the thermal fluid discharge tubule are connected to both ends ofa thermal fluid circuit having a micro pump and a heater providedoutside the micro chemical reactor 4, which is not shown in the drawing.Then, liquid such as silicon oil or gases such as water vapor, air andnitrogen are supplied as the thermal fluid into the thermal fluid flowpath 72, and the vaporization flow path 41. The reforming flow path 42and the carbon monoxide elimination flow path 43 are heated with heatenergy obtained from the supplied thermal fluid. However, also in thiscase, heating is carried out mainly with the heat energy generated bythe combustion through a catalyst combustion reaction in the combustionflow path 76 of the combustion section 10. The heat energy from thethermal fluid is used for secondary heating. The thermal fluid storesthe heat energy of the combustion section 10 and circulates in thethermal fluid flow path 72 as necessary.

[0073] In the embodiment described above, the grooves are respectivelyprovided in the first substrate 12 and the third substrate 14 to formthe flow paths, but as shown in FIG. 11, the vaporization flow pathgroove 57, the reforming flow path groove 58 and the carbon monoxideelimination flow path groove 59 that are continuously formed in onesurface of the second substrate 13, and the first substrate 12 whichcovers those grooves, may constitute the vaporization flow path 41 ofthe generation fuel vaporization section 7, the reforming flow path 42of the reforming reaction section 8 and the carbon monoxide eliminationflow path 43 of the carbon monoxide elimination section 9, respectively.Further, the combustion fuel vaporization flow path groove 51, thecombustion flow path groove 52 and the discharge flow path groove 53that are continuously formed in the other surface of the secondsubstrate 13, and the third substrate 14 which covers those grooves, mayconstitute the combustion fuel vaporization flow path 75, the combustionflow path 76, and the discharge flow path 77 respectively.

[0074]FIG. 11 is a cross sectional view along a line similar to the lineIII-III of FIG. 2, in which the generation fuel supply tubule 21, theoxygen supply tubule 23, the combustion fuel supply tubule 27, theelectrodes 33 and the discharge flow path 77 are not illustrated. Thesecond substrate 13 is a silicon substrate with excellent workabilityand relatively high thermal conductivity, and the first substrate 12 andthe third substrate 14 which are on and under the second substrate 13are made of glass whose thermal conductivity is lower than that of thesilicon substrate, and thus the vaporization flow path 41, the reformingflow path 42 and the carbon monoxide elimination flow path 43 can have aconfiguration that is easy to heat and capable of storing heat so thatthe heat is not extremely generated outside. The reforming catalystlayer 44 and the selective oxidative catalyst layer 45 have been formedon three surfaces of the groove, but may be formed on at least onesurface or more.

[0075] In the embodiments described above, the carbon monoxideelimination section 9 oxidizes carbon monoxide in accordance with theabove equation (3), but may oxidize it by an aqueous shift reactionrepresented by the following equation (6), and the carbon monoxideelimination flow path 43 may be provided with both parts where thechemical reactions of equation (6) and the equation (3) are caused.

CO+H₂O→CO₂+H₂  (6)

[0076] Water, which causes the aqueous shift of carbon monoxide, on aleft side of the equation (6) is contained in the generation fuelsection 2, and water which has not reacted in the above equation (2) maybe used, and water taken in by the by-product take-in section 107 fromthe fuel cell section 5 may also be used. Since the reaction of theequation (6) produces hydrogen, an amount of hydrogen supplied to thefuel cell section 5 can be increased, so that the part which causes thereaction of the equation (6) should preferably be provided closer to aside of the reforming flow path 42 than the part which causes thereaction of the equation (3).

[0077] In the embodiments described above, the slits 56 are continuouslyprovided in the first substrate 12, the second substrate 13 and thethird substrate 14, but in order to improve strength, the slits providedside by side with each other in the first substrate 12, the secondsubstrate 13 and the third substrate 14 may be displaced to be arrangedin such a manner that they do not overlap each other.

[0078]FIG. 12 is a perspective view of the partially broken fuel cellsystem 1 comprising the compact chemical reactor and fuel cell of thepresent invention.

[0079] As shown in FIG. 12, the fuel cell system 1 comprises a fuelstorage module 102 which stores the generation fuel 68 to be reformedand the combustion fuel 69 to be combusted, and a power generationmodule 103 which has the built-in micro chemical reactor 4 to generateelectricity using the generation fuel 68 stored in the fuel storagemodule 102. The micro chemical reactor 4 has the generation fuelvaporization section 7, the reforming reaction section 8, the carbonmonoxide elimination section 9, the combustion section 10, the thin filmheater section 11, the first micro pump 46 and the second micro pump 47.

[0080] The fuel storage module 102 has a substantially cylindrical case104. The case 104 can be detachably attached to the power generationmodule 103. A round through-hole 105 is formed at a head top portion ofthe case 104, and a first drain pipe 106 which allows by-product waterproduced by the power generation module 103 to flow is formed in aninner part of an outer periphery of the case 104. The by-productcollecting section 109 which stores water to be drained is disposed at abottom of the fuel storage module 102. The by-product collecting section109 is connected to a first drain pipe 106.

[0081] A fuel package 108 is detachably housed inside the case 104, andpart of an outer peripheral surface of the fuel package 108 is exposedfrom the outside of the case 104. The fuel package 108 further has thegeneration fuel section 2 in which the generation fuel 68 is sealed andthe combustion fuel section 3 in which the combustion fuel 69 is sealed.The fuel package 108 is a transparent or semitransparent columnar memberhaving an internal space, and is made of a biodegradable materialdegraded by bacteria or the like. As part of the fuel package 108 isexposed and the fuel package 108 is transparent or semitransparent, itis possible to easily check the presence and remaining amount of thegeneration fuel 68 and the combustion fuel 69 inside through the fuelpackage 108.

[0082] The generation fuel 68 is a mixture of a liquid chemical fuel andwater, and alcohols such as methanol and ethanol or carbon compoundscontaining a hydrogen element, for example, ethers such as diethyl etherand gasoline are applicable as the chemical fuel. In the presentembodiment, a mixture in which methanol and water are mixed is used asthe generation fuel 68.

[0083] The combustion fuel 69 is a liquid chemical fuel, and alcoholssuch as methanol and ethanol or carbon compounds containing a hydrogenelement, for example, ethers such as diethyl ether and gasoline areapplicable as the chemical fuel. In the present embodiment, a highconcentration of methanol is used as the combustion fuel 69.

[0084] A partition plate 111 which separates the generation fuel 68 fromthe combustion fuel 69 is formed inside the fuel package 108. A supplyport 110 for supplying the generation fuel 68 and the combustion fuel 69to the power generation module 103 is provided at the head top portionof the fuel package 108 in a manner to protrude to be inserted into thethrough-hole 105 of the case 104.

[0085] A supply pipe 112 extending in upward and downward directions ofFIG. 12 to be inserted in the supply port 110 is provided inside thefuel package 108. The supply pipe 112 extends from the bottom of thefuel package 108 to an edge of the supply port 110. Since the supplypipe 112 is divided into small parts by the partition plate 111, thegeneration fuel 68 between the supply pipe 112 and the partition plate111 moves upward by a capillary phenomenon to reach the first micro pump46. The combustion fuel 69 between the supply pipe 112 and the partitionplate 111 moves upward by the capillary phenomenon to reach the secondmicro pump 47.

[0086] A sealing film is provided inside the supply port 110, whichcloses the entire supply port 110 so that the generation fuel 68 and thecombustion fuel 69 do not leak in a state where intake nipple portions137, 138 of the power generation module 103 are not inserted, but theintake nipple portions 137, 138 of the power generation module 103 areinserted into the supply port 110 in order to break the sealing film,and the intake nipple portions 137, 138 communicate with the fuelpackage 108 so that they can take in the generation fuel 68 and thecombustion fuel 69, respectively.

[0087] The power generation module 103 includes an almost cylindricalcase 130. The micro chemical reactor 4 is disposed inside the case 130.The fuel cell section 5 is disposed on a periphery of the micro chemicalreactor 4 and on an outer peripheral side of the case 130. A by-producttake-in section 135 takes in part of the by-product produced by the fuelcell section 5 and supplies this to the micro chemical reactor 4 asnecessary. The control circuit section 20 electrically controls thoseabove.

[0088] A plurality of slits 131 for supplying oxygen in the air outsidethe power generation module 103 that is needed for power generation bythe fuel cell section 5 to the fuel cell section 5 is formed in a statearranged in parallel with each other outside the fuel cell section 5 andin an outer peripheral surface of the case 130.

[0089] A terminal 132 for supplying electric energy generated by thefuel cell section 5 to an external device is provided at the head topportion of the case 130. A plurality of air holes 133 for taking inoxygen necessary for the combustion section 10 of the micro chemicalreactor 4 to combust the combustion fuel 69 as well as oxygen necessaryfor the carbon monoxide elimination section 9 to oxidize carbon monoxideand for discharging carbon dioxide produced by the micro chemicalreactor 4 are formed on a periphery of the terminal 132 and at the headtop portion of the case 130.

[0090] A second drain pipe 134 is provided on the outer peripheral sideof the case 130. The second drain pipe 134 has a convex shape whose edgeprotrudes downward from the bottom of the case 130, and the convexportion can be received in a corresponding concave part in the firstdrain pipe 106 of the fuel storage module 102. The second drain pipe 134is a pipe for allowing by-product water produced by the fuel cellsection 5 to be distributed. The by-product water is discharged to theby-product take-in section 135 through the second drain pipe 134 and thefirst drain pipe 106.

[0091] The second drain pipe 134 is coupled to the by-product take-insection 135. A water introduction pipe 136 provided in the case 130leads to the second drain pipe 134 via the by-product take-in section135. The by-product take-in section 135 functions as a pump whichintroduces the by-product water produced by the fuel cell section 5 tothe micro chemical reactor 4 as necessary, and supplies a proper amountof water intended for the micro chemical reactor 4 to the waterintroduction pipe 136, and then discharges extra water to the seconddrain pipe 134. The sections requiring water in the micro chemicalreactor 4 include the reforming reaction section 8 which causes thereforming reaction of the above equation (2) and the carbon monoxideelimination section 9 which causes the aqueous shift reaction of theabove equation (6). The micro chemical reactor 4 reuses water thusproduced in the fuel cell system 1, thereby making it possible toheighten the concentration of chemical fuel except for water containedin the generation fuel 68 in the generation fuel section 2 of the fuelpackage 108, and increase an amount of produced hydrogen per unit volumeof the fuel, and also increase output of the fuel cell section 5 perunit volume of the fuel.

[0092] In the fuel storage module 102 and the power generation module103 as described above, when the fuel storage module 102 storing thefuel package 108 is attached to the power generation module 103, thesecond drain pipe 134 of the power generation module 103 is connected tothe first drain pipe 106 of the fuel storage module 102 on an outerperipheral side of an area where the modules 102, 103 are connected. Inthis way, the second drain pipe 134 communicates with the first drainpipe 106, thereby making it possible to let the by-product waterproduced by the power generation module 103 flow from the second drainpipe 134 to the first drain pipe 106 to be discharged to the by-producttake-in section 135.

[0093] The fuel applied to the fuel-reforming type fuel cell presentlyunder research and development may be a fuel which is at least a liquidfuel or liquefied fuel or gas fuel containing hydrogen elements and fromwhich electric energy can be generated by the fuel cell section 5 at arelatively high energy conversion efficiency, and fluid fuels that canbe satisfactorily applied include alcoholic liquid fuels such as ethanoland butanol in addition to methanol mentioned above, liquid fuels madeof hydrocarbons which are vaporized at ordinary temperature and atatmospheric pressure, for example, liquefied gases such as dimethylether, isobutane and natural gas (CNG), or a gas fuel such as a hydrogengas.

[0094] As described above, according to this invention, the flow pathsare provided inside the flow path structure and the flow paths areconstituted of a plurality of continued parts where different chemicalreactions take place, so that a plurality of chemical reactions can beefficiently caused continuously in plural kinds of flow paths, and thewhole reactor can be made simple and compact.

1. A chemical reactor comprising: a first reaction section which has afirst flow path and causes a first reaction in the first flow path; aheating section which heats the first reaction section; and a secondreaction section which has a second flow path and causes a secondreaction in the second flow path by heat of the heating sectiontransmitted via the first reaction section.
 2. The chemical reactoraccording to claim 1, wherein the first reaction and the second reactionare different reactions.
 3. The chemical reactor according to claim 1,wherein the second reaction is caused at a temperature lower than atemperature at which the first reaction is caused.
 4. The chemicalreactor according to claim 1, wherein the first flow path and the secondflow path are coupled.
 5. The chemical reactor according to claim 1,wherein the second reaction section has a vaporization reaction sectionwhich vaporizes a generation fuel, and the first reaction section has areforming reaction section which reforms the vaporized generation fuel.6. The chemical reactor according to claim 1, wherein the first reactionsection has a reforming reaction section which reforms the generationfuel, and the second reaction section has a carbon monoxide eliminationsection which eliminates carbon monoxide produced in the first reactionsection.
 7. The chemical reactor according to claim 1, wherein the firstreaction section and the second reaction section are formed on the samesubstrate.
 8. The chemical reactor according to claim 7, wherein heat ofthe heating section is transmitted from the first reaction section tothe second reaction section via the substrate.
 9. The chemical reactoraccording to claim 1, wherein a distance between the first flow path andthe heating section is shorter than a distance between the second flowpath and the heating section.
 10. The chemical reactor according toclaim 1, wherein the second flow path is disposed on a periphery of thefirst flow path.
 11. The chemical reactor according to claim 1, furthercomprising a substrate in which grooves configuring the first flow pathand the second flow path are formed.
 12. The chemical reactor accordingto claim 1, wherein the first reaction section and the second reactionsection are micro reactors.
 13. The chemical reactor according to claim1, further comprising: a thermometer section which measures temperatureof the heating section.
 14. The chemical reactor according to claim 13,further comprising: a control circuit section which causes the heatingsection to generate heat on the basis of temperature information of thethermometer section.
 15. The chemical reactor according to claim 1,wherein the heating section has a combustion section which performsheating by a combustion reaction.
 16. The chemical reactor according toclaim 15, further comprising a substrate on which the first reactionsection is formed, and wherein the combustion reaction heats the firstreaction section via the substrate.
 17. The chemical reactor accordingto claim 1, wherein the heating section has a resistive element.
 18. Thechemical reactor according to claim 1, further comprising: a thirdreaction section which has a third flow path and causes a third reactionin the third flow path by the heat of the heating section transmittedvia the second reaction section.
 19. The chemical reactor according toclaim 18, wherein the third reaction is caused at a temperature lowerthan the temperature at which the first reaction is caused.
 20. Thechemical reactor according to claim 18, wherein the third reaction iscaused at a temperature lower than the temperature at which the secondreaction is caused.
 21. The chemical reactor according to claim 18,wherein the third flow path and the first flow path are coupled.
 22. Thechemical reactor according to claim 18, wherein the third reactionsection has a vaporization reaction section which vaporizes thegeneration fuel, the first reaction section has a reforming reactionsection which reforms the vaporized generation fuel, and the secondreaction section has a carbon monoxide elimination section whicheliminates carbon monoxide produced in the first reaction section. 23.The chemical reactor according to claim 18, further comprising a singlesubstrate on which the first reaction section, the second reactionsection and the third reaction section are formed.
 24. The chemicalreactor according to claim 23, wherein the heat of the heating sectionis transmitted from the first reaction section to the second reactionsection via the substrate, and further transmitted from the secondreaction section to the third reaction section via the substrate. 25.The chemical reactor according to claim 18, wherein a distance betweenthe second flow path and the heating section is shorter than a distancebetween the third flow path and the heating section.
 26. The chemicalreactor according to claim 18, wherein the third flow path is disposedon a periphery of the second flow path.
 27. A chemical reactorcomprising: a plurality of substrates including first and secondsubstrates laminated on each other; a first reaction section which has afirst flow path between the first substrate and the second substrate,and causes a first reaction in the first flow path; a heating sectionwhich heats the first reaction section; and a second reaction sectionwhich has a second flow path between the first substrate and the secondsubstrate or between the second substrate and another substrate adjacentto the second substrate, and causes a second reaction in the second flowpath at a temperature, which is lower than a temperature at which thefirst reaction is caused, by the heating section.
 28. A fuel cell systemcomprising: a chemical reactor which comprises: at least two substrateslaminated on each other; a first reaction section which has a first flowpath between the substrates, and causes a first reaction in the firstflow path; a heating section which heats the first reaction section; anda second reaction section which has a second flow path between thesubstrates, and causes a second reaction in the second flow path at atemperature, which is lower than a temperature at which the firstreaction is caused, by the heating section; and a fuel cell whichgenerates electricity by use of a fuel reformed by the chemical reactor.